[Benjamin Lee Professorship Lecture] Skyrmions and their dynamics in helical magnets
* SPEAKERS
Name
Affiliation
E-mail
Prof. Dr. Naoto Nagaosa
Dept of Applied Physics, Univ. of Tokyo
* HOST(Applicant)
Name
Affiliation
E-mail
Jihye Jeong
jihye(at)apctp.org
* DATE / TIME
2012-08-21, 4:30PM
* PLACE
APCTP Seminar room (Hogil Kim Memorial Bldg.-512)
* ABSTRACT
We discuss the phase diagram of two-dimensional DM helical magnet under magnetic field. It is shown that SkX state is stable in a wide range of the T-H phase diagram. This is confirmed experimentally by Lorentz microscope recently. The coupled dynamics of the conduction electrons and SkX will be also discussed: (i) The topological Hall effect is induced by the spin chirality, (ii) The Skyrmion trajectories bend away from thedirection of the electric current (the Skyrmion Hall effect),(iii) A new dissipation mechanismin non-collinear spin textures can lead to a much faster spin relaxation than Gilbert damping, (iv) The dispersion of phonons in the SkX are k^2, and (iv) the pinning effects of SkX by impurities is very weak, and it can move with very small current density. This work has been done in collaboration with JiadongZang, Maxim Mostovoy, M. Mochizuki, Jung Hoon Han,J. H. Park, K. Nomura, X. Z. Yu, Y. Onose, N. Kanazawa, Y. Matsui, Y. Shiomi, and Y. Tokura.
